ASME B18.16.4-2008 pdf – Serrated Hex Flange Locknuts 90,000 psi (Inch Series)
ASME B18.16.4-2008 pdf – Serrated Hex Flange Locknuts 90,000 psi (Inch Series).
This Standard covers the general, dimensional, and mechanical performance requirements for low strength carbon steel, case hardened, regular and large serrated flange locknuts (inch series), recognized as American National Standard.
2 COMPARISON TO ISO STANDARDS
There is no inch series ISO standard for these products at this time.
For definitions of terms relating to fasteners or component features used in this Standard, refer to ASME B18.12.
4 REFERENCE STANDARDS
The following is a list of publications referenced in this Standard.
ASME B1.1, Unified Inch Screw Threads
ASME B1.3, Screw and Thread Gaging Systems for Dimensional Acceptability — Inch and Metric Screw Threads (UN, UNR, UNJ, M, and MJ)
ASME B18.12, Glossary of Terms for Mechanical Fasteners
ASME B18.18.2M, Inspection and Quality Assurance for High-Volume Machine Assembly Fasteners
ASME Y14.5M, Dimensioning and Tolerancing
Publisher: The American Society Of Mechanical Engineers (ASME), Three Park Avenue, New York, NY 10016-5990; Order Department: 22 Law Drive, P.O. Box 2300, Fairfield, NJ 07007-2300
ASTM F 606, Test Methods for Determining the
Mechanical Properties of Externally and Internally
Threaded Fasteners, Washers, Direct Tension
Indicators, and Rivets
ASTM F 812, Specification for Surface Discontinuities of Nuts, Inch Series
ASTM F 1941, Electrodeposited Coatings on Threaded Fasteners [Unified inch Screw Threads (UN/UNR)]
ASTM F 2282, Standard Specification for Quality Assurance Requirements for Carbon and Alloy Steel Wire, Rods, and Bars for Mechanical Fasteners
ASTM F 2328, Standard Test Method for Determining Decarburization and Carburization in Hardened and Tempered Threaded Steel Bolts, Screws, and Studs
Publisher: ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959
(a) Unless otherwise specified, all dimensions in this Standard shall be as specified in Tables I and 2, and sections 6 through 9. All dimensions in this Standard are in inches and apply before plating or coating is specified. When a plating or coating is specified, the finished product dimensions shall be agreed upon between the supplier and purchaser.
(b) Symbols specifying geometric characteristics are in accordance with ASME Y14.5M.
The configuration of the serrations shall be at the discretion of the manufacturer, provided the performance requirements as specified in para. 12.2 are met.
7 TOPS OF NUTS
Tops of nuts shall be flat and chamfered. The length of chamfer at hex corners shall be from 5% to 15% of the basic thread size. The surface may be slightly convex or rounded.
8 TRUE POSITION OF HEXAGON TO TAPPED HOLE
At maximum material condition (MMC), the axis of the hexagon shall be located at true position with respect to the axis of the thread pitch diameter within a tolerance zone having a diameter equivalent to 4% of the maximum width across flats.
Tapped hole shall be countersunk on the bearing face and may be countersunk on the top. The maximum countersink diameter shall be the thread basic (nominal) major diameter plus 0.030 in. for 3/ in. nominal size nuts and smaller, and 1.08 times the basic major diameter for nuts larger than in. No part of the threaded portion shall project beyond the bearing surface.
Threads shall be Unified coarse or fine thread series (UNC or UNF series) Class 2B, in accordance with ASME B1.1.
Inspection shall be based on System 21 of ASME B1.3.
11 MATERIAL AND HARDNESS
Unless otherwise specified, nuts shall be manufactured from carbon steel in accordance with ASTM F 2282. The nuts shall have a case hardness of HR 15N 78-90 on the surface of the nut in accordance with ASTM F 2328. For referee purposes, case hardness shall be measured in the serrations.